October 1, 2013

Cable-free transmission by light of extremely high data rates

Terrestrial Free-Space Optical Links over distances of 10 km at a rate of 10 Gbit/s

Sending extremely high data rates by light with no need for optical cables directly through the air at lightening speeds: with the optical free-space data transfer system developed by the Fraunhofer Heinrich Hertz Institute huge amounts of data can be transmitted in both directions in just a few seconds.

Fraunhofer HHI's optical transmitter and receiver enable point-to-point transmission of digital information via light through the air at a rate of 10 Gbit/s over a distance of up to 10 km. Most of the commercial systems for optical free space data transmission
(also known as Free Space Optics or FSO systems) transmit data at a rate
of up to 2.5 Gbit/s over just a few kilometers.

Areas of Application for terrestrial Free Space Optical Links

These systems can be used in all places where high bitrate links are required and where there is a free line of sight but where fiber optic cables cannot be used. Whether it’s between two buildings or between a fixed and a mobile station, Fraunhofer HHI’s FSO system offers a reliable and robust means of transferring large amounts of data with its exact positioning of transmitter and receiver and rapid adaptability to changing movement patterns. If fiber optic cables are damaged or destroyed by natural disasters, for instance, FSO offers a rapid means of bridging the information gap and transmitting vital information – like from a rescue plane to the central control unit. Transfer of large data volumes from a base station to an express train is also possible with this link-up, and video and photos can be fully transferred in just a few seconds.

Overall, Fraunhofer HHI's solution comprises

  • Numerical simulation of the complete system
  • Design, fabrication and characterization of components
  • Optimization of transmitter/receiver configuration
  • Installation and characterization of optical transmitters and receivers
  • Experimental proof-of-concept of the whole design
  • Enhancement of the optical transmitter and receiver

Projections by market researchers ElectroniCast Consultants predict that the market for FSO systems will double in size by 2018. The prototype developed by Fraunhofer HHI will show under laboratory conditions that a robust optical communications link between a transmitter and receiver with a data rate of up to 10 Gbit/s over a distance of 10 km is indeed possible.